Diesel engine injector



Nov. 11, 1941.`

M. E. HOVER 2,262,181

DIESEL ENGINE INJECTOR Filed Sept. 16, 1938 Aw@ A INVENT OR.' M0072? Halie@ ATTORNEY.

Patented Nov. 11, 1941 DIESEL ENGINE INJECTOR Monte E. Hover, Culver City, Calif., assignor of one-half to Robert W.

Calif.

Fulwider,` Los Angeles,

Application September 16, 1938, Serial No. 230,275

(Cl. 12S-138) 18 Claims.

My invention relates generally to fuel injectors for internal combustion engines, and more particularly to injectors for engines of the Diesel, semi-Diesel, and similar types.

The major object of my invention is to provide an injector which delivers an accurately measured amount of fuel to the combustion chamber of an internal combustion engine.

Another object of my invention is to provide simple and easilyv operable means for varying the amount of fuel so delivered.

Still another object of my invention is to perform these functions without the use of high speed mechanismand with apparatus which is small and easily attached to the engine.

These and other objects of my invention will be apparent from the following description of a preferred form thereof, and from the accompanying drawing, in which:

Fig. l is a view of the injector, partly in section and partly cut away, showing the device as cut away along its axis,

Fig. 2 is a plan view of the injector, showing the location of the air and fuel inlets,

Fig. 3 is a detail section taken at 3-3 in Fig. 2, showing the fuel inlet and the fuel passage cut into the piston,

Fig. 4 is a plan view taken at 4-4 in Fig. 1 showing a portion of the combustion chamber of the engine, this being omitted in other views for the sake of clarity,

Fig. 5 is a view taken at 5-5 in Fig. 4, showing the shape of the piston,

Fig. 6 is a view of an optional form of piston positioner, showing location of bearings, and

Fig. 7 is a perspective view of the preferred form of piston positioner.

Referring now to the drawing, and particularly to Fig. 1 thereof, the numerals I0 and II indicate the upper and lower sections, respectively, of a separable circular housing, said sections being provided with annular-shaped bearing plates 36 and 3l which are parallel to each other. A rotor, preferably in the form of a cylinder block I2, is mounted on a shaft I8 in said housing and rotates between said bearing. plates 36 and 3l. The cylinder block VI2 is circular in shape and of such dimension that its peripheral face make sealing contact with the central section of the inner wall of said housing. In the block I2 are one or more radially positioned cylinders I3, each cylinder sealed at its outer end by Asuitable means, such as a. plug I 4 having an orifice I5. In each cylinder is a piston I6 proand preferably also along its side wall. The drive shaft I8 rotates in bearings I`9 and 20, and is connected by any suitable means to the engine (not shown) with which the injectoris associated. Suitable piston positioning means is disposed at the center of the block I2 and in the preferred form of my invention takes the form of a fluted wedge member 2I, axially slidable along the shaft I8 under the control of the operator, and adapted to rotate with the drive shaft. In this form of my invention, I prefer to make the upper portion of the drive shaft I8 hollow and insert a spindle 22 therein, said'spindle being provided with suitable means, such as a double collar 23 and its engaging member 24, for moving the spindle axially to any desired position within' the shaft. An elongated key-Way 25 is provided in the shaft I8, and the fiuted wedge member 2I is keyed to the spindle 22 by a key 40 in a manner such that it may slide.V along the shaft I8 as the spindlevis moved axially, while revolving with the shaft. Radial grooves 26 are cut into the rotating cylinder block I2 adjacent its axis, so that the flutes of the wedge member 2| fit therein and cause the cylinder block I2 to rotate with the shaft I8.

In my preferred form, the housing I0 is provided with a fuel inlet 21 and connection'thereto, said inlet leading through a passage 28 to suitable sealing means in the bearing plate 36, such as avpierced block 29 which bears against the rotating cylinder block l2, the pierced block being held against the latter by resilient means, such as a flat spring 30. Each cylinder I3 is provided with a hole 3I adapted to register with Y the opening in the pierced block 29 when the cylinder reaches the correct angular position, so that a continuous passageway for the fuel from inlet 2'I into the cylinder I3 is then provided. The previously mentioned groove I1 connects with the hole 3l, so that even when the piston fluted wedge member respect to the shaft I8.

vided with a channel I1 cut across its outer face 55 is in its outermost position, a flow of fuel into the cylinder through groove I"l is assured.

The position of the piston I 6 in the cylinder I3, and hence the amount of fuel admitted to the cylinder, is determined by the position of the 2|. Each flute of the latter in its corresponding groove 26 bears against a tail-like projection 32 the latter outwardly or permitting it to return nearer to the axis of the cylinder block, dependingfupon the axial position of the wedge with By thus providing a positive contact relationship between the piston positioning means and lthe pistons, I secure exon each piston, forcing of une :un injected. into thecombustienchamber of the associated engine Thehousing I provided with an air iniet sa, constructed similarly to the fuel man. lIn the housing, and aligned with the cylinder plug orice I5, is' an orifice 34 leading into the combustion chamber of the engine to which fuel is to be delivered. The air inlet 33 is located so as 'to admit air into the injector cylinder I3 while the latter is in the proper posii'on to discharge the resulting fuel and air mixture into the combustion chamber 45 through4 the orifice 3 4. In

one adaptation of myinvention, the fuel is forced into the engine combustion chamber at about before its pistons dead center and continuesy until the said piston is 25 to 30 past dead center. In

the six cylinder injector shown, fuel 'is admittedinto the injector cylinder approximately 60j before-it reaches the point of discharge.v

A drain plug 38 may be located in the lower portion ofthe housing II to permit draining of any fuel that may have accumulated therein, and

' af bracket 39, or similar means may be provided A f to facilitate fastening the injector to the engine. '-Any air under pressure remaining vin the cylinder after rthe fuel has beenrejected, escapes between the rotor I2 and the housing It, as will any air remaining in the cylinder" when the fuel is injected, the air escaping through small spaces normally being .present through irregularities in the' machining of the surfaces. While the rotor I2 makes substantially sealing fit with the housing II,4 these irregularities are nevertheless always present, and hence the air under pressure in the cylinder is Apermitted to escape, and a slight.

amount of fuel will leal: out of the cylinder.

necessitating the use of the drain `plug 38.

In Fig. 6 'is shown an optional method of providing means for sliding the uted wedge member 2l along the-shaft I8. In this form of my der; and means for forcibly electing said fuel invention, the shaft I8 is'grooved at itsextremity and rotates with it by reason of said splines. At the outer extremity of the hollow shaft 35 is a tofadmit splines or keys on the wedge member 2I,which,in'this oase is a continuation of a hollow shaft 35, which fits over the drive shaft I8 collar arrangement 23 similar to that already described, and adapted to move the fluted wedge member 2l along the shaft I8 While it is rotating to thus vary the quantity offuel injected into the engine combustion chamber. The operation yof the injector is as follows: With the fluted wedge member 2l at the desired 'throttle setting and' the injector pistons lI6.` in

their corresponding positions, fuel is introduced through the fuelinlet 21 at a suitable pressure as for instance from to 150 pounds per square inch from a' supply 4 6 through the hole 3| and channel- I1 into the injector cylinder I3. The pressure'at whichthe-fuel is admitted is suilicient inder, creating extreme turbulence therein. At

this point, the cylinder plug orifice I5 passes the combustion chamber orifice 3l.' and the fuel in a completelyatomized state is injected into the.

combustion chamber of the engine by the compressed air. The iiow of air through the cylinder I3 preferably continues for a sullicient length of time to scavenge the cylinder and said orifices.

As will be seen, the injector of my invention, while running at a relatively slow speed, can nevertheless properly supply an accurately measured amount of fuel to a high speed engine; and

4in the injector illustrated, the speed of the njector drive shaft would be but one-sixth of the engine speed of a. two-stroke-cycle engine, and one-twelfth the engine speed of a four-strokecycle engine.

It is to be understood of course that the values given herein are for purposes of illustration only.

and that other values may be used as required by the particular engine and fuel.

The device illustrated and described herein is the preferred form of my invention, and it is to be understood that modifications may be made which are included within the spirit of the invention, as for example cutting away portions of the cylinderblock to decrease weight, making the rotorof cylindrical shells held together by bands and rings, or modifying the piston positioning means to meet certain requirements of use.

I claim as my invention:

l. A fuel injector for internal combustion engines which includes: a housing; a rotor mounted on a shaft within said housing and provldediwith a generally radially disposed cylinder and a free piston therein; means for limiting the inward travel of said piston within said cylinderimeans for injecting fuel under pressure into said cylinfrom said cylinder.

2. A device as described in claim 1 in which the means for limiting the inward travel of said l piston comprises a wedge-shaped member slidably carried on the shaft of said rotor.

3. A device as described in claim l in which said piston is substantially cylindrical in shape and has a groove cut across its outer face.

V4. A device as described in claim 1 in which the'meansfor limiting the inward travel of said piston comprises a wedge-shaped member slidably carried on the shaft of said rotor, and-in which said piston has a groove ycut across its outer face and along its side wall.

5. A fuel injector for internal combustion engines which includes: a housing; a rotor mountedon a shaft in said housing and provided with agenerally radially disposed cylinder and to move the injectorlpiston I6 back until it is stopped by the wedge member 2| if the piston has been moved out by centrifugal force or other piston therein; adjustable means for limiting the inward travel of said piston within said cylinder; means for injecting fuel into said cylinder; and means for blowing said fuel from said cylinder.

6. A device as described in claim 5 in which the means for limiting the inward travel of said piston comprises a wedge-shaped member slidmeans. The channel I1 cut into the wall and 65l face of the piston I6 permits the fuel to enter the injector cylinder even if the injector piston is in itsoutermost position, as itmaybe when idling at closed throttle position. Asthe rotating ,cylinder block I2 revolves, the hole 3I is closed'and the fuel-filled cylinder I3 passes to t'ne point Ywhe'reritshole 3I registers with fair inlet 33, where compressed air under relatively high pressure, such as from 2000 to 4000` pounds per square inch,

from a supply l1 is admitted to the injector eyl-l the rotor shaft is hollow and the means for limiting the inward movement of said piston comprises a wedge-shaped member slidably carried on said hollow shaft, said shaft having an elongated key-way therein and a spindle in the center thereof, said spindle having a key passing through said key-way and into said wedgeshaped member.

10. A device as described in claim in which the means for limiting the inward travel of said piston includes a wedge-shaped member on (a hollow shaft slidably mounted on said rotor shaft, said slidable shaft being provided with splines or keys which engage with corresponding key-ways on said rotor shaft causing both shafts to rotate as one. f

1l. A fuel injector for internal combustion engines which includes: a-housing; a rotating block having a cylinder therein, mounted in said housing; a shaft driving said block by means of a member having wedge-shaped flutes and axially slidable thereon; a piston within said cylinder, said piston having a groove out across its outer face and along its side wall; means for axially moving said wedge-shaped member to vary the limit of the inward motion of said piston; a plug in the outer end of said cylinder provided with an orifice; means for lling the remaining space between said piston and said plug in said cylinder with fuel; and compressed air means for then ejecting-said fuel through a suitable outlet in said housing. i

l2.. A fuel injector for internal combustion engines which includes: a housing; a rotor in said housing provided with a plurality of cylinders and pistons therein; adjustable means for limiting the inward travel of said pistons within said cylinders; means for injecting fuel under pressure into said cylinders, and means for l forcibly electing said fuel from said cylinders directly into the combustion chamberoi' said engine.

13. A device as defined in claim 12 in which the means for limiting the inward travel of saidpistons is a iluted wedge-shaped member slidably carried on the injector shaft.

i 14. A fuel injector for internal combustion engines which includes: a housing; a rotor mounted on a shaft in said housing and provided with a generally radially disposed cylinder and piston therein; adjustable means for limiting the inward travel of said piston within said cylinder; means for admitting fuel under pressure into said cylinder; and means for admitting air under pressure into said cylinder whereby said fuel is discharged therefrom.

l5. A fuel injector for internal combustion engines which includes:V a housing; a rotor mounted on a shaft in said housing and provided with a generally radially disposed cylinder; a pistonA within said cylinder having a groove cut across l its outer face and along its side wall; adjustable means for limiting the inward travel of said piston within said cylinder, said means comprising a wedge-shaped member slldablycarried on the rotor shaft; means for admitting fuel under pres.

sure into said cylinder; and means for admitting air under pressure into said cylinder whereby said fuel is discharged therefrom.

16. A fuel injector' for internal combustion engines which includes: a. housing; ya rotor in said housing with a cylinderl and a free piston therein; adjustable means for limiting the inward travel of said piston within said cylinder; a fuel inlet in said housing leading to the rotor and radially equidistant from the rotor axis with a passageway in said rotor leading to said cylinder; an air inlet in said housing angularly displaced from said fuel inlet but also at the same distance radially from the rotor axis; and an outlet in said housing adapted to be connected to a cylinder of said internal combustion engine, said air inlet and said outlet being disposed so that when said injector cylinder is connected to said inlet, it is also connected to said outlet.

17. A fuel injector for internal combustion en gines which includes: a housing having a pair of parallel annular bearing plates; a rotorhaving a substantially radially disposed cylinder therein, mounted in said housing between said bearing plates; a piston within said cylinder, said piston having a substantially cylindrical shape with a groovecut across its outer face and along its side wall; a shaft driving said rotor by means of a iluted wedge-shaped member axially slidable thereon 'and adjustable to limit the inward travel of 'said piston; a plug in the outer end of said cylinder provided with an orifice; a fuel inlet in said housing connectable to said cylinder whereby the space between said piston and said plug may be filled with fuel; a compressed air inlet located in said housing and connectable to said cylinder; and an outlet in said housing adapted to be connected toa cylinder of said internal combustion engine, said air inlet and said -plates; a shaft driving said rotor by means of a iluted wedge-shaped piston-travel-lirniting member axially slidable thereon; a piston within each of Said cylinders, each piston being provided with a tail-like projection adapted to bear against said piston-travel-limiting member so as to limit the inward travel of said piston; a. plug in the -outer end of each cylinder provided with an oriy lice; a fuel inlet in said housing connectable through resiliently mounted sealing means to each. cylinder successively whereby the space between said piston and said plug may be lled with fuel; a compressed air inlet angularly-disposed from said fuel inlet, located in said housing, and

connectable to each cylinder successively; and an outlet in said housing adapted to be connected to a cylinder of said internal combustion engine, said air inlet and said outlet being disposed so that when said injector cylinder is connected to said inlet it is also connected to said outlet.

MONTE E. HOVER. 

